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making successful efforts to provide elementary education, but this does not excuse it for 
the almost total neglect of the health of the Eskimos. 

On the contrary, as is well known, the importation of reindeer has proved a great success. 
Congress appropriated $300,000 to buy them; and their progeny, now in Alaska, are esti- 
mated to be worth $3,000,000. 

The author's circuit is shown on an outline map of Alaska. He also reproduces LefBng- 
well's map {U. S. Geol. Survey Professional Paper log, 1919) and pays tribute to the fine 
work that Lefiingwell accomplished in the careful triangulation of this northern coast, 
"for which he must always be remembered in the annals of geography." 

Cyrus C. Adams 

History of the Biogeographical Problem of Discontinuous . Distribution 

Nils von Hofsten. Zur alteren Geschichte des Diskontinuitatsproblems in der 
Biogeographie. Index. Reprint from Zool. Annalen, Vol. 7, 1916, pp. 197-353. 

This essay on the theories of the discontinuous distribution of plants and animals is 
limited to the living world and does not consider the life of the past ages. The presentation 
is clearly and interestingly written by a biologist along historical lines. It begins with the 
theories of the Greeks as set forth by Hippocrates and Aristotle, who thought the distri- 
bution to be due to differences in the local climates, and follows the more essential ideas 
down to the present time. For a while the church stimulated this research because of the 
riddle of the wide distribution and variability of man, but in the end it fought the conclu- 
sions of the naturalists. 

Modern views began with the discovery of America, with its plants and animals which 
are different from those of Europe. Some continued to explain this difference by special 
local creations, and in fact Louis Agassiz (1850-1859) held to the creation theory to the 
end of his life. Buffon (1749-1756) is sometimes regarded as the originator of modern 
views in regard to biogeography. The way was further indicated by Cuvier (1815), Lyell 
( 1 830-1 833), Heer (1845), and Forbes (1846) and was modernized by Hooker, De Candolle, 
Darwin, and Wallace. Now we know that the organisms are where they are because of 
local genetic developments out of antecedent stocks, conditioned by their variable dis- 
persion and evolution along varying routes of travel and climate, and that this variation 
was brought about in the main by the geologic changes in the configuration of the land 
surfaces and their oceanic boundaries. 

Charles Schuchert 

Rock Structure and Landscape Form 

Karl Sapper. Geologischer Bau und Landschaftsbild. vi and 208 pp.; ills., index. 
Die Wissenschaft, Vol. 61. Friedr. Vieweg & Son, Brunswick, 1917. M. 7.20. 9x6 

This semi-popular book, the outgrowth of lectures delivered in 1916, is the work of an 
experienced explorer in tropical America, Australasia, and elsewhere, who was professor 
of geography at the German university of Strassburg for several years up to the end of 
the war and who was then transferred to Wiirzburg. The first half of the book discusses 
the interaction of underground structures and surface processes in the production of the 
manifold landscapes of the earth; the second half is occupied with generalized descriptions 
of various types of landscape as affected by climate. 

The first half is novel in some respects, as in giving in the introductory pages brief accounts 
of the odors and sounds that are associated with certain landscapes and in detailing the 
changes of landscape appearance under varying illumination, as at morning, noon, and 
evening, in clear and in stormy weather, in winter and in summer. The motive here seems 
to be to call attention to items that are commonly overlooked. But when we read in one 
passage that the chief source of illumination is the sun, by which the moon as well as the 
earth is lit up; in another that the change from day to night affords the maximum contrast 
of light and darkness; in a third that among other sources of terrestrial illumination are 
the aurora borealis, volcanic eruptions, lightning, and prairie fires (shooting stars are 
omitted); and in a fourth that fireflies and burning natural gas are generally too faint 


to light up the landscape, the question arises whether the enumeration of such matters is 
a mark of originality and profundity or merely of perseverance. 

The systematic discussion of landscapes divides their elements into inorganic and organic 
groups; but instead of the natural order of arrangement which assigns first treatment to 
the inorganic elements, because they constitute the environment in which most of the 
organic elements have their being, we find the organic elements are here given precedence. 
Perhaps as a result of this order of presentation, organic forms are not clearly treated as 
conditioned by the inorganic; there is not sufficient emphasis given to the relationships that 
exist between the earth and its inhabitants, although such relationships are of the highest 
significance in actual landscapes. Instead, various relatively trivial items are here again 
instanced, such as the spray spouted by whales at sea. The harmless statement that 
"Perhaps nothing affects the beauty of a landscape more than vegetation" is regarded as of 
sufficient originality to be credited to its author, Masius H. Wagner, who is quoted as 
having calculated (he must have had much time to spare) that if the plants of the earth 
were evenly distributed over its entire surface they would form a layer 4.4. mm. in thick- 
ness, to which the animals would add 0.5 mm. But no reference is made to the important 
studies made by American and other ecologists concerning the slowly flowing adjustment 
of floras and faunas to the gradual change of surface forms in a down-wearing land area, 
although the principles thus established are as beautiful as they are significant. Surely 
these principles are more important than Wagner's calculations; they cannot be omitted 
if landscapes are to be appreciatively studied. 

In the chapters on land forrns, the attempt is made to treat them in a broad philosophical 
manner. Constructional forms are first described, and the effect of erosion in modifying 
them is then introduced; but the discussion is so incomplete that few clear ideas can be 
gained by readers not already familiar with the subject. As if conscious of this deficiency, 
the author offers a delusive excuse for not assuming fuller responsibility for an explanatory 
treatment; namely, that the book is not concerned with theoretical analyses. But in reality 
the results of theoretical analyses, and for the most part of good analyses as far as they go, 
are found on many pages. For example, in treating of the transformation of initial fortns of 
disorderly structure into their derivatives, the author points out that, even after the down- 
wearing of such masses to an almost level surface, the direction of rivers and of "many other 
features" will still reveal the attitude of the underlying rocks (p. 57). Exception need not 
be taken to the manifestly theoretical nature of this statement, but only to its vagueness, 
for inquiring readers will be dissatisfied not to know how it happens that river courses on* 
worn-down surfaces indicate underground structure, and not to know what kinds of other 
features give similar testimony. 

The more serious aspect of Sapper's delusion as to his method of discussion not being 
theoretical is that, like those untrained "practical" persons who complacently assure us that 
they do not theorize, he fails to distinguish between safe and unsafe theoretical conclusions. 
Thus reference is made to the plains of Russia (p. 43) as if they departed from their initial 
form only by the incision of valleys, and the Jura mountains are cited on three different 
pages (pp. 33, 46, 49) as if they were but little modified by erosion since their folding; yet 
evidence has been brought forward, by Philippson and Bruckner among others, which shows 
that both the Russian plains and the Jura anticlines are now in a fairly advanced stage of 
a second cycle of erosion, following peneplanation in an earlier cycle. In spite of the title 
of the book, its first half, in frequently failing to give the reader a clear understanding of 
visible land forms, does not embody the essence of what Passarge very well calls Landschafts- 
hunde, "a new branch of geography that has at last secured for itself the place that it should 
have taken long ago" (Beschreibende Landschaftskunde, 1919, p. i). . 

Another curious characteristic of Sapper's method is a mistrust of the indispensable mental 
faculty of deduction as an aid in reaching an understanding of land forms. The mistrust 
is expressed in several homilies, which intimate that not enough is yet known about the 
manner of action of various external processes upon various underground structures to 
make it possible in all cases to use the deductive method safely. There cannot be two 
opinions about these "safety first" generalities, for physiographic research has surely not 
yet solved all its problems. For that very reason the important thing for every physiog- 
rapher to do is to try to carry forward the investigation of land forms, inductively and 
deductively, toward more and more assured results. 

The negating quality of treatment exhibited in the unsuccessful effort to exclude theoreti- 
cal analyses and deductive explanations is encountered again in an attempted exclusion of 


explanatory terms, that give indication of the origin of land forms, in favor of neutral terms 
that give no such indication; yet frequent use is made of such terms as volcano, landslide, 
moraine, and various others which have the origin of the forms that they designate embedded 
in them. And a similar negating quality is seen in the condemnation of block diagrams 
because, as vegetation is ordinarily not indicated upon them, they might be taken to 
represent desert landscapes; yet no unfavorable comment is made on the use of mere pro- 
files or structural sections, such as are found in Richthofen's "Fijhrer" or in Penck's "Mor- 
phologic," although such figures are much less helpful to the uninformed reader than even 
rudely drawn block diagrams, in which structure, profile, and surface are all indicated. 
Sapper solves the diagram question for his own book handily enough by having no diagrams 
at all, thus leaving his readers to make out his meaning from the text alone as best they can. 
As already noted, the second half of Sapper's book, which describes eight climatic types 
of landscape, is easier and better reading than the first half, because the author here pre- 
sents for the most part general descriptions, in which he succeeds, and gives but secondary 
attention to systematic explanations, for which he is apparently less qualified. The eight 
types are: humid tropical, open tropical, subtropical desert, moist temperate, dry temperate, 
high mountains of middle or low latitudes, subpolar and polar, and sea and coastal land- 
scapes. The examples presented are well chosen, but the implication that certain classes 
of structure are associated with certain types of climate may mislead the reader. Here, as 
in the first part of the book, it is curious to note that, with very few exceptions, no authors 
or observers other than Germans are cited. Whether this is because the university library 
at Strassburg was poorly stocked with geographical books, or whether it is a consequence 
of nationalistic introspection during the Great War cannot be told. 

W. M. Davis 

The Physiological Effect of the Air on the Human Body 

C. W. B. NoRMAND. The Effect of High Temperature, Humidity, and Wind on the 

Human Body. Diagrs. Quart. Journ. Royal Meteorol. Soc, No. 193, Vol. 46, 1920, 
pp. 1-14 (discussion, pp. 12-14). I-ondon. 

The deadliness of the simoon has long been a source of speculation, but now the question 
appears conclusively solved. It is neither the high temperature alone that kills nor the 
strong dust-filled wind that suffocates, but the two in combination, which brings more heat 
to the human body than it can lose even though exerting its maximum powers of providing 
for evaporation. The author presents a detailed discussion of the katathermometer with 
a wetted surface and of the ordinary wet-bulb thermometers as indicators of possible limits 
of human life under different conditions of temperature, humidity, and wind velocity. The 
wet-bulb thermometer constantly supplied with moisture is taken as the better index of 
human responses. With a certain maximum rate of provision of moisture for evaporation 
there comes a limiting temperature above which, no matter how dry the air is, the tempera- 
ture of the wet bulb can no longer be maintained at blood heat by evaporative cooling. 
The stronger the wind, the lower this limiting temperature is. As there is a limit to the 
amount of water the human body can supply for evaporation in a given time, the stronger 
the wind, the lower must be the air temperature if weather conditions are not to prove fatal. 

On a calm day 120° F. may be easily endurable under the conditions of extremely low 
humidity characteristic of a desert in daytime; but if a simoon comes on, even though the 
wind may actually reduce the temperature by mixing the heated surface air with cooler 
air above, the air becomes fatal. However, if the face, hands, and feet are buried in the 
clothing, and the simoon does not last over an hour or two, the reduced wind velocity at 
the skin and the slow rise of temperature due to body heat and conduction may prevent 
fatal body temperatures being reached. 

Among a group of men some will get heat strokes much sooner than others. This is 
due to physiological differences and also to local effects of clothing. Heat strokes may come 
from unbearable heat and humidities over portions of the body poorly ventilated on account 
of clothing, or through exhaustion of the sweat glands, or derangement of the bodily heat 
regulatory apparatus. 

Charles F. Brooks